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191.
The stimulating effect of antiparkinsonian drugs, talipexole and bromocriptine, on the striatal postsynaptic dopamine receptors were studied by measuring contralateral rotational behavior in rats. The nigro-striatal dopamine system of rats was degenerated by unilateral injection of 6-hydroxydopamine (6-OHDA, 8 micrograms/rat) into substantia nigra. By subcutaneous administration, talipexole at 0.16 mg/kg and bromocriptine at 10.24 mg/kg induced significantly increased rotational behavior to the contralateral direction to the lesioned side. The onset of the effect was 30 min for talipexole and 90 min for bromocriptine. By intragastric administration, talipexole at 0.4 mg/kg and bromocriptine at 20.48 mg/kg significantly increased the rotational behavior, and the onset of the effect was 60 min for talipexole and 180 min for bromocriptine. Rotational behavior induced by talipexole was suppressed by a D2 antagonist, sulpiride (40 mg/kg, s.c.), but not by a D1 antagonist, SCH23390 (1 mg/kg, s.c.). In contrast, rotational behavior induced by bromocriptine was suppressed by both sulpiride and SCH23390. These results indicated that when the nigrostriatal dopaminergic functions are disrupted, talipexole stimulates the striatal postsynaptic dopamine receptors at much lower doses than bromocriptine. Also it was indicated that the stimulating effect of talipexole is solely mediated by dopamine D2 receptors, whereas the effect of bromocriptine is mediated by both D1 and D2 receptors.  相似文献   
192.
Strictureplasty is an alternative to extensive and/or multiple small bowel resections in the surgical treatment of Crohn's disease. We here report a series of 22 patients (12 M-10 F-mean age years 28). All patients had non perforative form of Crohn's disease lasting for a mean of 8 years. Nine out of 22 had previous intestinal resections. A total of 201 stenosis was identified during per-operative examination (mean per patient: 9). Only tight stenoses (diameter < 2 cm) were treated while others were left untouched. Eighty-three stenoses were treated by short strictureplasty and 24 by long strictureplasty using steel thread. One or several resections were simultaneous performed in 15 patients. Mortality was nil. A post operative abscess without loosened suture was drained. The mean follow-up in the 22 patients was 36 months (range: 12 to 96). Relief of obstructive symptoms was achieved in all patients. Symptomatic recurrence occurred in 9 patients (40%) and 5 (22%) needed reoperation. In one case haemorrhagic ulceration developed within a long strictureplasty and in 4 others stenosis developed in plasty areas but also in previous healthy areas. Thus stricture-plasty is intended not to replace resection but rather to serve as a useful adjunct to the existing surgical options in the treatment of Crohn's disease, especially when short bowel syndrome is a consideration.  相似文献   
193.
OBJECTIVE: MR coronary angiography is most often performed using two-dimensional techniques. Although three-dimensional (3D) acquisitions do have important advantages, they take too long for a single breath-hold and are thus susceptible to respiratory motion artifacts. The purpose of this study was to investigate the accuracy of a unique respiratory-gated 3D MR angiographic technique in identifying the proximal coronary arteries in patients suspected of having coronary artery disease. In addition, we investigated the capability of this technique to detect proximal stenoses. SUBJECTS AND METHODS: We performed a prospective blinded study in 20 patients who were referred for conventional coronary angiography. A cardiac-gated 3D gradient-echo sequence with fat suppression was used. Retrospective respiratory gating was performed using navigator echoes of the diaphragm position. Using multiplanar reformatting, two independent readers blindly analyzed the data sets for visualization of major coronary arteries, lengths of imaged segments, and detection of significant stenoses (> 50% occlusion of the luminal diameter by conventional angiography). RESULTS: Seventy-seven of 80 (96%) coronary arteries were positively identified. In one patient, an anomalous coronary anatomy was readily identified and confirmed by conventional angiography. The average lengths of the imaged segments of the right, left main, left anterior descending, and left circumflex coronary arteries were 58 +/- 13 mm, 9 +/- 5 mm, 59 +/- 16 mm, and 24 +/- 10 mm, respectively. Overall sensitivity for the detection of stenoses was low (38%), with a specificity of 95%. Interobserver agreement was 0.92, with a kappa value of 0.65. CONCLUSION: Respiratory-gated 3D MR angiography allows accurate identification of proximal coronary arteries and may be valuable for 3D imaging of coronary anomalies. Further technical improvements are required to enhance the value of the technique in detecting stenoses.  相似文献   
194.
A non-contact strain measurement method that could be used in a physiological environment was adapted to determine accurately the mechanical properties of bone. The technique of laser speckle photography was applied to record in-plane surface displacements. An automated image analysis system, based on a Fast Fourier Transform algorithm, was developed for data acquisition and its accuracy and precision verified. It was established that the technique could be used at magnifications of up to 60x , providing an ultimate resolution of approximately 1 microm. Displacement measurements on cortical bone submerged in water were demonstrated, which is of great value in determining the true physiological properties of bone.  相似文献   
195.
OBJECTIVE: To determine the contemporary antibiotic susceptibility profile of vertically acquired group B streptococcal isolates. METHODS: Susceptibility to ampicillin, penicillin G, erythromycin, clindamycin, cefazolin, and gentamicin was assessed by two methods, minimal inhibitory concentration and disc diffusion. RESULTS: The susceptibility profiles of 119 colonizing and eight invasive strains of group B streptococcus isolated from January 1996 to September 1997 at two hospitals in Birmingham, Alabama-University of Alabama at Birmingham and Cooper Green-were studied. Minimal inhibitory concentration determinations indicated that all colonizing strains were susceptible or moderately susceptible to ampicillin and penicillin G. Resistance was noted by at least one strain to each of the other antibiotics; all were resistant to gentamicin, whereas 27 (21%) were resistant to erythromycin, five (4%) to clindamycin, and one (1%) to cefazolin. All of the eight invasive strains were susceptible or moderately susceptible to ampicillin, penicillin G, clindamycin, and cefazolin; one (13%) was resistant to erythromycin, and all were resistant to gentamicin. Disc diffusion results generally were concordant with minimal inhibitory concentration results, although by disc diffusion fewer isolates were classified as susceptible, and more as moderately susceptible, to ampicillin and penicillin G than by minimal inhibitory concentration. CONCLUSION: Universal susceptibility of group B streptococcus to members of the penicillin family supports the continued use of penicillin G or ampicillin for early onset neonatal group B streptococcal disease prevention. For patients allergic to beta-lactam agents, clindamycin (4% resistance) may be a better alternative than erythromycin (21% resistance).  相似文献   
196.
Alternative therapy for refractory leukemic patients is being increasingly adopted. Circumvention of multidrug resistance represents a strategy that has been taken into account when conventional chemotherapy failed. In this work a group of 15 refractory, heavily pretreated, patients was enrolled in a circumvention protocol including etoposide (ETO) and cyclosporin A (CSA). All patients received etoposide prior to this schedule. Toxicity to circumvention protocol was acceptable and only one serious side-effect was observed. Two hematological clinical responses were seen, both of which were positive to P-glycoprotein immunostaining and exhibited in vitro modulation by CSA in cultures using the thymidine incorporation assay. Three out of four patients negative for P-glycoprotein achieved a minor response. Three out of six clinical failures were also negative for Pgp immunostaining one of which exhibited sinergistic effect between ETO and CSA. Our study suggests that hematological response to ETO and CSA association can be obtained in intensely pretreated leukemic patients. Several factors may affect the response such as clinical status before this therapy. Additionally, it also suggests that not all CSA effects on the combination ETO-CSA can be attributed to Pgp modulation.  相似文献   
197.
198.
Excitatory amino acid neurotoxicity has been proposed to cause the neostriatal neuronal degeneration of Huntington's disease (HD); N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA), and kainate receptors have been hypothesized to play important roles in this process. We have recently reported a loss of neurons in layer VI of the cerebral cortex in HD. Using quantitative autoradiographic methods, we have now measured NMDA, AMPA, and kainate receptor binding in the frontal cerebral cortex of the brains of controls and individuals with HD. We find no change in NMDA receptor binding but a selective decrease in kainate and AMPA receptor binding in layer VI. These data suggest that cerebral cortical neurons possessing kainate or AMPA receptors may be selectively vulnerable in individuals with HD.  相似文献   
199.
A 64 year old woman presented with persistent and severe symptoms due to recurrent aspiration pneumonias associated with oesophageal reflux. She had had multiple miscarriages and her son at birth had widely spaced eyes (hypertelorism), hypospadias, bilateral undescended testes, and an imperforate anus. Her daughter has mild hypertelorism and her daughter's son had neonatal inspiratory stridor, hypospadias and hypertelorism, all features now recognised as typical of the Opitz oculo-genito-laryngeal syndrome. This syndrome is genetically heterogeneous with autosomal dominant (linked to chromosome 22q21) and X-linked (linked to Xp22) inheritance. This family's history and genetic linkage data are consistent with linkage to Xp22. The proband is a manifesting carrier of this syndrome; her history of recurrent aspiration is probably secondary to pharyngeal neuromuscular incoordination aggravating gastro-oesophageal reflux. Obtaining a family history gives a vital clue to the diagnosis of Opitz oculo-genito-laryngeal syndrome. It is also suggested that this condition should be included in the differential diagnosis of recurrent aspiration pneumonia.  相似文献   
200.
The induction of a calcifying matrix is of great interest in the restoration of bone defects. In a previous in vitro study we demonstrated that a collagen sponge constituted of type I collagen fibrils, chondroitin sulfates, and hydroxyapatite crystals induces an earlier and a more abundant synthesis of a new extracellular calcifying matrix than do other biomaterials such as collagen or hydroxyapatite alone. Bone mineral contains various amounts of magnesium ions, either adsorbed at the surface of apatite crystals or incorporated inside the crystal structure. Magnesium is known to reduce the degradation rate of tricalcium phosphate ceramics and to influence the crystallization of mineral substance. Thus we evaluated two sponges modified with different substituted apatites. The substituted low magnesium-containing apatite sample decreased the osteoinductive properties of the sponge whereas the substituted high magnesium-containing apatite sample had a toxic effect on bone cells and prevented the formation of any extracellular matrix. Such a toxic effect can be explained by the presence of large numbers of magnesium ions released into the culture medium even though at physiological level magnesium is able to promote bone mineralization and to control the growth of hydroxyapatite crystals. Thus collagen sponges containing hydroxyapatite remain one of the most appropriately evaluated biomaterials used for the restoration of periodontal pockets and bone defects.  相似文献   
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